Yeah, he did officially. Here is the blurb from the ATP Player's Weekly, dated Feb 11, 2008:
Paul Goldstein announced his retirement from professional tennis last week. Paul will start working with a clean energy company in the San Francisco Bay Area. He reached a career high No. 58 in singles (Apr 2006) and No. 40 in doubles (Feb 2007). Paul has served in the Player Council since July 2006.
It's a shame that he has not gotten more press for this, he was a good player and he's a very decent man.
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